Lifting device for lifting heavy loads, in particular derailed rail vehicles

ABSTRACT

The invention relates to a lifting device for lifting heavy loads, e.g. derailed rail vehicles, for permanent or temporary installation, having at least one cylinder, in particular hydraulic cylinder, for actuating a mechanical ram, in which device cylinder  2  and ram  3  are separate from one another and the ram  3  is accommodated in a guide tube  4.

[0001] The invention relates to a lifting device for lifting heavyloads, e.g. derailed rail vehicles, for permanent or temporaryinstallation, having at least one cylinder, in particular hydrauliccylinder, for actuating a mechanical ram. In concrete terms, the presentinvention relates to a so-called “internal jack”.

[0002] Vehicles (e.g. trams, underground trains, etc.) which, in theevent of derailment, are impossible to lift and/or move from outside thederailed vehicle (e.g. when in tunnels) are recovered using so-called“internal jacks”. Internal jacks are understood to mean lifting deviceswhich are fitted permanently or temporarily in the floor area in theinterior of the vehicle and by means of which recovery measures can becarried out from outside even where accessibility is extremelyrestricted. Known internal jacks are designed as single-acting hydrauliccylinders or telescopic cylinders which are generally attached in thefloor of the vehicle. Therefore, a floor sleeve provided for thispurpose is arranged on the vehicle. The cylinder is installed head-firstin this floor sleeve. In operation, the piston rod, when actuated,extends downwards and lifts the vehicle body so that it can then bemoved.

[0003] In low-floor vehicles, which are now being used to an increasingextent, suitable installation of the internal jacks is becoming more andmore difficult due to the restricted space available.

[0004] The object of the present invention consists in providing alifting device which can be used for low-floor vehicles and, at the sametime, has a high level of safety against buckling and flexuralload-bearing capacity combined with perfect running.

[0005] This object is achieved, in the lifting device of the generictype, by the fact that cylinder and ram are separated from one anotherand the ram is accommodated in a guide tube. The invention makes itpossible to achieve a lifting device which provides sufficient force andvery stable guidance in the area of the ram and which can beaccommodated in particular in the outer wall area of low-floor vehicles.

[0006] Advantageously, the ram is designed as a hollow ram. This firstlyreduces its weight and secondly simplifies fitting of the ram. On theother hand, the strength of the ram is maintained.

[0007] The tool insert, which may in particular be designed as anexchangeable tool insert, is situated at the front end of the hollowram.

[0008] To attach the lifting device to the vehicle, the guide tubecomprises a catch, in particular a bayonet catch. The catch isadvantageously situated in the floor area of the vehicle.

[0009] According to a further configuration of the present invention,cylinder and ram are connected to one another in an articulated manner.This prevents elastic distortions in use from being transmitted from theram area to the cylinder area, where they would lead to damage to therunning faces or seals.

[0010] Such an articulated connection can be produced in a particularlysimple manner by using a ball socket and ball cap in the area of thecontact face between ram and piston rod of the cylinder.

[0011] Advantageously, the articulated movement of ram with respect topiston rod is spring-loaded, specifically, by way of example, by meansof at least one spring element which is provided between cylinder andram and may be designed as a spring element which acts in the axialdirection.

[0012] According to a further configuration of the present invention,the ram and the piston rod of the cylinder can be connected to oneanother by means of a threaded bolt which can be introduced axially viathe inside of the hollow ram.

[0013] Furthermore, according to a refinement of the invention, aholding ring, e.g. in the form of a clasp nut, is provided in the areaof the connection between piston rod and ram. The holding ring holdstogether the area where the piston rod of the cylinder and the guidetube meet. To avoid adverse effects from dirt, a seal is providedbetween holding ring and cylinder. The seal has the further advantagethat the rat cannot itself be rotated with respect to the cylinder inthe load-free state as a result of slight shaking, and therefore theconnection between holding tube and vehicle cannot be releasedunintentionally.

[0014] The holding ring is designed or dimensioned in such a way that itallows a pivoting movement of the ram, including guide tube, withrespect to the cylinder.

[0015] The outer sides of the cylinder and of the holding ring areexpediently aligned, so that the diameter of the cylinder is notexceeded, thus ensuring problem-free installation.

[0016] Furthermore, it is possible, in particular in the case of alifting device which remains permanently on the vehicle, to provide asecuring device for fixing the position of cylinder and/or ram.

[0017] The securing device used is, for example, at least one securingpin in the area of the cylinder and/or ram and/or holding ring. Thesecuring pin may in this case advantageously be arranged so as to run inthe radial direction.

[0018] The lifting device according to the invention is veryparticularly suitable for installation in the outer wall area of thevehicle, in particular, for example, in the section column of the outerwall, The locking position of the lifting device is preferably providedin the floor area of the vehicle.

[0019] An expedient configuration of the present invention is explainedin more detail with reference to the drawings, in which:

[0020]FIG. 1 shows a sectional illustration through the lifting deviceaccording to the present invention;

[0021]FIG. 2a shows a sectional illustration on line E-F in FIG. 1;

[0022]FIG. 2b shows a sectional illustration on line C-D, and

[0023]FIG. 2c shows a sectional illustration on line A-B in FIG. 1.

[0024] In FIG. 1, reference numeral 1 denotes the lifting device, e.g. aso-called “internal jack”, in its entirety. The lifting device 1comprises a cylinder 2 with a piston rod 9 which is guided in thecylinder 2 by means of a piston 21. The piston rod 9 runs in a guidepart 19 at the widened end of the cylinder 2. On the opposite side,there is a closure cover 20 and a connection, which is provided in theclosure cover 20, with a hydraulic hose 17 and quick-fitting coupling14. A corresponding quick-fitting coupling 16 is also provided in thewidened area of the cylinder 2, for connection to a hydraulic hose 18.

[0025] The hydraulic hoses 17, 18 are connected to a reversing valve anda pump with reservoir, which are not shown in FIG. 1.

[0026] According to the present invention, cylinder 2 and ram 3 areformed separately from one another. To this end, a ram, in the form of ahallow ram, is provided and is guided in a guide tube 4. A holding ring,in particular in the form of a clasp nut 12, is situated on the outerside of the guide part 19 and adjoining guide tube 4.

[0027] Piston rod 9 and ram 3 are connected to one another by means of athreaded bolt which is arranged centrally, with a spring element 10,which acts in the axial direction, interposed between them. In addition,at its end side the piston rod 9 is designed as a ball cap 8 and theadjoining end side of the ram 3 is designed as a ball socket 7, with theresult that ram 3 can be pivoted to a certain extent with respect topiston rod 2. The holding ring is in this case to be designed in such away that it allows a certain degree of pivoting of ram 3, guide tube 4and cylinder 2.

[0028] In its end area facing towards the ram 3, the cylinder 2 has awidened diameter which, in this area, corresponds to the diameter of theholding ring or of the clasp nut 12. The ram 3 is guided in a guide tube4. A catch, in particular bayonet catch 5, is situated on the guide tube4 for the purpose of locking the guide tube 4 in the floor area of avehicle (not shown).

[0029] An encircling seal 13, in the form of an O-ring seal, is situatedbetween the widened area of the cylinder 2 and the holding ring, whichseal ensures that it is impossible for any dirt to pass between cylinderand holding ring. Furthermore, the seal 13 has the additional functionof ensuring that the ram 3, including guide tube 4, cannot itself rotatewith respect to the cylinder 2 in the load-free state as a result ofslight shaking, and as a result the bayonet locking on the bayonet catch5 cannot be released when this is not desired.

[0030] According to the invention, the piston rod 9 and the ram 3 areconnected to one another in an articulated manner, specifically, by wayof example, by means of a ball cap 8 which is provided in the area ofthe contact face between piston rod 9 and ram 3 and interacts with aball socket 7. Piston rod 9 and ram 3 are connected to one another bymeans of a threaded bolt 11 which can be screwed in axially. Inaddition, the threaded bolt 11 acts on an axial spring element 10. Inorder to ensure articulated mobility of the ram 3 with respect to thepiston rod 9, the hole for the threaded bolt 11 is oversized in the areaof the ram 3.

[0031] Furthermore, the clasp nut 12 is likewise dimensioned in such away that it allows the ram 3 to pivot with respect to the piston rod 9.An individually exchangeable tool insert 6 is situated on the front sideof the ram 3. The securing pin 15 prevents any rotation between claspnut 12 and guide tube 4.

[0032]FIG. 2a shows the arrangement of two securing pins 22 in the areaof the widened part of the cylinder 2 (cf. in this respect FIG. 2a).Furthermore, two securing pins 23 are also provided in the area of theram 3 (cf. FIG. 2b), with the result that the two components, whichaccording to the invention are separate from one another, are secured inposition even in the event of vibration, preventing them from becomingdetached of their own accord.

[0033]FIG. 2c shows the design of the bayonet catch 5 for fixing theposition of the ram 3 on the vehicle.

[0034] The lifting device 1 according to the invention is expedientlyfitted head-first in the outer wall area 1, in particular in the area ofthe section column of the outer wall, and the guide tube 4 of the ram 3is coupled, at the bayonet catch 5, to the bayonet socket of thevehicle.

[0035] The invention makes it possible to use lifting devices, inparticular so-called “internal jacks”, on rail vehicles where there isonly a very limited amount of space at the bottom (low-floor vehicles)without having to accept any reduction in the stability of the liftingdevice.

LIST OF REFERENCE NUMERALS

[0036]1 Lifting device

[0037]2 Cylinder

[0038]3 Ram

[0039]4 Guide tube

[0040]5 Bayonet catch

[0041]6 Tool insert

[0042]7 Ball socket

[0043]8 Ball cap

[0044]9 Piston rod

[0045]10 Spring element

[0046]11 Threaded bolt

[0047]12 Clasp nut

[0048]13 Seal

[0049]14 Quick-fitting coupling

[0050]15 Securing pin

[0051]16 Quick-fitting coupling

[0052]17 Hydraulic hose

[0053]18 Hydraulic hose

[0054]19 Guide part

[0055]20 Closure cover

[0056]21 Piston

[0057]22 Securing pin

[0058]23 Securing pin

1. Lifting device for lifting heavy loads, e.g. derailed rail vehicles,for permanent or temporary installation, having at least one cylinder,in particular hydraulic cylinder, for actuating a mechanical vat,characterized in that cylinder (2) and ram (3) are separated from oneanother and the ram (3) is accommodated in a guide tube (4).
 2. Liftingdevice according to claim 1 , characterized in that the ram (3) isdesigned as a hollow ram.
 3. Lifting device according to claim 1 or 2 ,characterized in that the ram (3) has a tool insert (6) on its frontside.
 4. Lifting device according to one of the preceding claims,characterized in that a catch, in particular a bayonet catch (5), isprovided on the guide tube (4) for connection to the vehicle.
 5. Liftingdevice according to one of the preceding claims, characterized in thatcylinder (2) and ram (3) are connected to one another in an articulatedmanner.
 6. Lifting device according to claim 5 , characterized in that,in order to achieve an articulated bearing, a ball socket (7) and ballcap (8) are provided in the area of the contact face between ram (3) andpiston rod (9) of the cylinder (2).
 7. Lifting device according to claim5 or 6 , characterized in that at least one spring element (10) actsbetween cylinder (2) and ram (3).
 8. Lifting device according to claim 7, characterized in that an axial spring element is provided as thespring element (10).
 9. Lifting device according to one of the precedingclaims 6-8, characterized in that ram (3) and piston rod (9) can beconnected by means of a threaded bolt (11) which can be introducedaxially via the inside of the ram (3).
 10. Lifting device according toone of the preceding claims 6-9, characterized in that a holding ring isprovided in the area of the connection between piston rod (9) and ram(3).
 11. Lifting device according to claim 10 , characterized in thatthe holding ring is a clasp nut (12).
 12. Lifting device according toclaim 10 or 11 , characterized in that a seal (13) is provided betweenholding ring and cylinder (2).
 13. Lifting device according to one ofthe preceding claims 10-12, characterized in that the holding ringallows a pivoting movement of the ram (3), including guide tube (4),with respect to the cylinder (2).
 14. Lifting device according to one ofthe preceding claims 10-13, characterized in that the respective outersides of the cylinder (2) and holding ring are aligned with one anotherin the area of the transition.
 15. Lifting device according to one ofthe preceding claims, characterized in that a securing device for fixingthe position of cylinder (2) and/or ram (3) is provided.
 16. Liftingdevice according to claim 15 , characterized in that at least onesecuring pin (15, 22, 23) is provided, as the securing device, on thecylinder (2) and/or ram (3) and/or holding ring.
 17. Lifting deviceaccording to one of the preceding claims, characterized in that thelifting device is provided for installation in the outer wall area ofthe vehicle.
 18. Lifting device according to one of the precedingclaims, characterized in that the locking position of lifting device andvehicle is provided in the floor area of the vehicle.